December in Jacksonville averages a daily high of 15.4°C with nights around 3.6°C. Expect roughly 9.9 wet days totalling 95.8mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Jacksonville is March–May.
Based on NEW RIVER MCAF, NC US (5.2km), 1995–2024. 27 years of December data.